The present invention relates generally to a rotationally asymmetric optical system, and more particularly to a rotationally asymmetric optical system that is of size small, and resolution good, enough for use on all sky cameras, all sky projectors, etc., designed to form on an image plane an image having a full 360°-direction angle of view or project an image located on the image plane onto a full 360°-direction angle of view, and that enables, for instance, an image in a specific direction to be picked up or projected on a more enlarged or reduced scale than an image in other direction.
Various full-panoramic optical systems using a catoptric or catadioptric system rotationally symmetric about a center axis to obtain a full 360°-direction (full-panoramic) image have been known from, for instance, Patent Publications 1-13.
In particular, Patent Publication 7 refers to a full-panoramic optical system of the zoom type adapted to implement zooming by the movement, transformation, and replacement of a reflecting mirror that forms the catoptric optical system.